United States
Environmental Protection
Agency
Office of Research and
Development
Washington, DC 20460
Office of Solid Waste and
Emergency Response
Washington, DC 20460
vyEPA
SITE FACTS
Location: St. Louis Park; ' ,
, Minnesota < V/ /"' , ; ,
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Laboratories/Agencies: U.8.
EPA Risk Reduction
~ Engineering Laboratory (RREL),
, Superfund Innovative > »
Technology Evaluation (SITE) > ^
Program, U.S^ EPA Region 5, >
Minnesota Pollution Control
" Agency,- ' - \ "
Media and Contaminants:
Polycyclie aromatic' >
hydrocarbons (PAHs)'in soil
Treatment: Bioventing
Date of Initiative Selection:
October 1992-, ' ' ' '
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Objective: To evaluate the
effectiveness of bioventing -
"PAH^ontaminatedsoiT -> ,
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Bioremediation Field Initiative
" Contacts: Paul McCauley and
' Richard Brenner/U.S..EPA
' RREL, 26 West.Martin Luther
King Drive, Cincinnati, OH ,
45268 , ' , ," , ' }
Regional Contact: Daryl
Owens, U.S.,EPA Region 5, \ >
,! Waste Management Division, 77
1 West Jackson Boulevard, r, -.^
', Chicago, IL 60604," / ' "J V ''
EPA/540/F-93/510H
September 1993
Bioremediation Field
Initiative Site Profile:
Reilly Tar and Chemical
Corporation Superfund Site
Background
This Bioremediation Field Initiative project is under way in St. Louis
Park, Minnesota, at the former site of Reilly Tar and Chemical Corpo-
ration's coal tar distillation and wood preserving plant. From 1917 to
1972, wastewater discharges and dumping from this plant contami-
nated about 80 acres of soil and the underlying ground water with
wood preserving wastes. In 1978, the Minnesota Department of
Health discovered significant concentrations of polycydic aromatic
hydrocarbons (PAHs) in six municipal drinking water wells neigh-
boring the Reilly Tar plant. St. Louis Park currently is pumping and
treating the contaminated ground water plume, but without an effort
to control the source of PAHs, pumping and treating might be neces-
sary for several hundred years.
This Initiative project is evaluating bioventing of PAH-contaminated
soil through the U.S. EPA Superfund Innovative Technology Evalu-
ation (SITE) Program and the U.S. EPA Risk Reduction Engineering
Laboratory's (RREL's) Biosystems Program. Bioventing has proven
effective at remediating lightweight petroleum distillates such as JP-4
jet fuel; this is the first evaluation of bioventing's effectiveness for
remediation of larger molecular weight hydrocarbons.
Characterization
The SITE program conducted a preliminary site characterization,
including soil sampling, soil gas monitoring, and in situ respiration
testing, in August 1992. Soil sampling revealed PAH contamination
in sandy vadose soil ranging from 2 to 10 ft below the surface! Soil gas
monitoring and respiration tests indicated that the soil's aerobic
microbial activity and air permeability are high enough for successful
bioventing.
Field Evaluation
In November 1992, baseline soil sampling was conducted and a
full-scale bioventing system installed on a 50-ft by 50-ft plot (see
Figure 1). A control plot of equal size and contaminant levels also was
established to gauge the effectiveness of the bioventing system. The
T£^ Printed on paper that contains at least
Va^y 50'percent recycled fiber.
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Flow
Control
Rotometer
Ql - Gas Injection Vent
GS - Gas Sample Probes
T-Temperature Probes
WL- Water Lavel Well
Figure 1. Layout ofbioventing installation on experimental plot.
system consists of one air injection well with
screening 5 to 10 ft below ground level (see Figure
2), a 2.5 hp blower, a network of 48 soil gas sam-
pllngprobes, and a system to monitor soil tempera-
ture and ground water elevation. The blower and
vent well deliver 100 ft3 of air per hour to the
contaminated soil.
Personnel from the City of St. Louis Park will moni-
tor subsurface temperature, as well as oxygen and
carbon dioxide levels, every 2 weeks. In situ respi-
ration tests will be conducted four times per year.
At the completion of the project, final soil samples
will be collected from the experimental and the
control plots.
Pressure Gauge
PVC Pipe
2" OD, Schedule 40
Sand Pack
Screened
Section
Figure 2. Schematic of air injection vent well.
Status
The demonstration project is expected to last 3
years, at which point it is estimated that soil core
samples will show at least a 27 percent reduction in
PAH levels. If bioventing successfully remediates
PAHs at this rate, complete remediation of the site
would take 10 to 15 years should large-scale
bioventing be undertaken. The results of this study
will determine whether bioventing can be consid-
ered at Superfund sites as a cost-effective treatment
technology for remediating PAH-contaminated soil.
*' i ** * < * > <*'' * '-"'C ' " ' , _, >
The Bioretnediation Field Initiative was established in 1990 to expand the nation's field experience in bipremediatibn technologies.
The Initiative's objectives are to more fully document the performance of full-scale'applications of, bioremediatio'n; .provide >
technical assistance to regional and state" site managers; and provide information on treatability studies, design/ and operation of *
bioremediation projects. The Initiative currently is performing field evaluations of bioremediation" at eight other'hazardous waste ''
sites: Libby Ground Water Superfund site, Libby, MT; Park City Pipelirie>Park 6ity, KS; Bendix Corporation/Allied Automotive
Superfund site, St. Joseph, MI; West KL Avenue Landfill Superfund site/Kalamazoo, MI; Eielson Air Force, Base^ Superfund site, '>
Fairbanks, AK; Hill Air Force Base Superfund site, Salt Lake'City, UT; Escambia Wogd Preserving Site1Brookhaven, Brookhaven,
MS; and Public Service Company, Denver, CO. To obtain profiles,on these additional'sites* or to be added ^o the Initiative's mailing
list, call 513-569-7562. For further information on the Bioremediation Field Initiative, contact FraifcKremer, Coordinator, Bioreme- -
diation Field Initiative, U.S. EPA, Office of Research and Development, 26 lAfest Martin Luther King Drive, Cincirma'ti/OH £5268;, -
or Michael Forlini, U.S. EPA, Technology Innovation Office, Office ol Solid Waste and Emergency Response, 401, M Street,
Washington,DC20460. 4 , * v" " '/,* '» \,-, -" >! ,«'-.,;' -/-' ,
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